/*
 * Copyright (c) 2011, Nikolaus Moll
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * * Neither the name of the gradecalculator.net nor the
 *   names of its contributors may be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */
package net.gradecalculator.grade.de.impl;

import net.gradecalculator.plugin.grade.interfaces.IGradeValidator;

public final class GradeValidator implements IGradeValidator {
	private static final float MIN = 1;
	private static final float MAX = 4;
	
	private static GradeValidator instance = null;
	
	private GradeValidator()
	{
	}
	
	public static GradeValidator getInstance()
	{
		if (instance == null) {
			instance = new GradeValidator();
		}
		
		return instance;
	}
	

	@Override
	public boolean isValid(final String grade) {
		try {
			return isValid(GradeUtil.stringToFloat(grade));
		} catch (final NumberFormatException e) {
			return false;
		}
	}

	public boolean isValid(final float f) {
		return ((f >= MIN) && (f <= MAX));
	}
}
